The computer files and data stored on file servers or workstations can be lost after a data loss event. For example, the computer files and data stored on a file server or a workstation may be accidentally deleted by end-users, intentionally corrupted by the malicious acts of outsiders, or destroyed by a disaster, such as a fire or earthquake. It is therefore desirable for computer files and data stored on a file server or a workstation to be backed up periodically by a backup and recovery system, so that they may be restored after a data loss event. However, designing a backup and recovery system poses many challenges, including privacy issues and producing a backup and recovery solution that is cost-effective.